Improvement in furnaces and furnace-doors



WILLIAM. ARENA MARTIN, on LONDON, ENGLAND, AisieNdg-or oNnHALF' His RIGHT 'ro JOHN Asuonor'r, or BROOKLYN, YORK.

IMPROVEMENT IN FURNACES AND FURNACE-DORS.

Specification forming part of Letters Patent No. l50,592, dated May 5, 1874 application filed l February 18, 1874.

To all whom 'it may concern:

VBeit known that I, NVILLIAM ARENA MAR- TIN, of London, England, civil engineer, have invented Improvements in Furnaces and Furnace-Doors, reference being had to the accompanyingV drawing forming a part of this specification, and in Which- Figure l is a horizontal section of a steamboiler furnace with my improvements applied to the same. Fig. 2 is a longitudinal vertical section on the `line x w, Fig. l. Fig. 3 is a transverse vertical section on the line yy, Fig. 2. Fig. 4 is a front elevation of the said furnace.

Like letters indicate the same parts throughout the drawing.

My said invention consists, chiefly, in the peculiar construction and arrangement of the furnace-door,whereby the said door is so supported as to open inwardly or outwardly, and admits the air in such a manner that it will all pass through, and not above, the fuel on the lire-bars; also, in the combination, with a furnace-door opening inward, of an inner plate,

inclining downward toward the grate for the y purpose of directing the air through the fuel on they grate-bars, causing it to penetrate the f'uel, mix with the gases, and thus produce intense heat before rising or entering the iiues, causmg perfect combustion, and, consequently, preventing the emission of smoke or gases; also, in the combination of a furnace door,

opening both inward and outward, with a coun ter-balance, whereby the door will remain in whatever position it may be placed without retaining devices, and which, besides being a most convenient feature for fire-grates generally, is of special advantage for marine boilers, as its position is -not affected by the rol]- ing of the ship, and its opening and closing movement or intermediate adjustment is instantly made; also, in the construction of the 'fire-grate of separate bars, rectangular in their cross-section, and with square ends projecting outside of and beyond the front of the furnace, whereby they may be turned completely over bya spanner-key, and by which each separate bar can be easily revolved and kept in proper space without grooved bearers, withdrawn in a horizontal position, and put in place again while the furnace is in use, and freeing or frame c of the said furnace-door.

the grate from dross and'clearing the spaces for the free admission of air without opening the furnace-door, and in this way prevent a 1 be turned over and over to present each of its four sides to the action of the iire, and to allow them to be taken out and put back again without any trouble with the re or the grate 5 also, in the combination of a furnace-door, opening either inward. or outward, with side openings, and side air-passages constructed to communicate with said openings andthe interior rear of the furnace, for the purpose of admitting air to effect a more complete combustion whether the door be opened inward or outward. I

I construct my improved furnacedoor a with a horizontal axle or spindle, b, at the top part, resting in bearingsmade in the cheeks The said axle or spindle b has a counter-balance weight, d, at each end, land is so arranged in its supports that the furnace-door will open either inwardly orV outwardly with equal facility, and will remain in any position in which it is left. By opening the furnace-door a a few inches inwardly, as shown in Fig. 2, the air is caused to enter and pass through the fuel, and to mingle with the gases produced therefrom in the process of combustion, before they rise from the fuel, causing them to ignite and to be perfectly developedbefore leaving the furnace, instead of leaving the furnace in the condition of smoke. tween which and the said door the air enters the furnace, in the manner abovev described. In some cases I make openings e in the frame of the said furnace-door, which openings lead into horizontal passages or channels fin the brick-work at the sides of the furnace. Y From each of these passages I make a lateral passage, or two or more lateral passages, g, for the air. By this construction the air, besides entering as above described, enters through the said openings in the frame of the furnacedoor, and passes along the said passages or channels into the furnace, as indicated by the arrows. I

My improved furnace-door is not restricted b is a plate, be

to its use in combination with a furnace ofthe construction shown in the drawing, although the said furnace and door are :ulvantagcously used in combination, as described.

I employiron iire-larslnfrom one inch to about one inch and a half in thickness. These bars are placed in the furnace below the level of the frame of the said furnace-door. They are supported upon transverse bearers t', and project outside the front of the furnace, as shown in Fig. 2, a-nd I prefer that some should project slightly beyond the other, thelong and short bars being placed alternately. By this arrangement the said bars are left 'entirely free at their ends for expansion. Each bar can be turned round to free it from'the dross or clinkers which adhere to it, a Spanner or key being applied to the bar for this purpose.

As will be seen, by referring to Fig. 3, my improved furnace is so constructed that it is wider at the top than at the bottom, so that the two sides a are inclined or sloping. This construction of the furnace economizes the heat, and renders the furnace more effective in heating the boiler.

As the door hangs from the top instead of the side, it will swing either inward or outward to any angle required, and, when set as shown in Fig. 2 of the drawings, will cause the air to enter at the lower part only by impinging upon and being deiiected by the inclined plate b; and as air at the common temperature is heavier than the heated gases i11- side it penetrates the fuel, becomes flame, and produces a very marked eifcct upon the combustion of the fuel, and by obtaining the maximum heat of the furnace reduces the labor of the stoker and economizes the fuel. The balancing feature of the door is produced by securing the weights d upon the axis of the door, so that they will be eccentric to said axis and project therefrom in the same radial line, as shown in Fig. 4, and as these weights are designed to be equal in weight to that of the door, they therefore ei'eet its complete counter-balance, and are provided with handles, by which to adjust the door. The door is hung upon two side plates, c c, which project and curveor incline downward to the base of the door, which is made to conform to the opening between these plates, and when open inward, the` air rushing 1n will strlke the lnclined face of the door, and thus be forced downward, the side plates preventing its lateral escape.

So elfectually docs this plan keep the door and its frame cool that the door is usually made of ordinary sheet-iron, which has been found to be sufficiently durable for the purpose. The door when made is an entirety, complete in itself, with counterpoise, and only requires attachment to the furnace-front opening, and as such is a new article of trade and manufacture, applicable to every kstyle of furnace or coal-burning heater.

The fire-bars h being lengths of wroughtiron simply placed upon the knife'edges of the bearers 17, each bar can be easily revolved with i little or no friction, and by their 'square projecting ends, each bar can be turned by means of a key-Spanner, and the whole set can be thus turned in about one minute. The bars being square in their cross-section, are thereby kept in proper space with each other, because their angles in turning them strike each other, and thus keep them spaced without having them seated in socket-bearers.

By this arrangement, also, each bar can be lifted from its bearer by simplyinsert-ing beneath each bar a flat bar the thickness of the air-spaces, for breaking up bituminous and cooking coals; and this iron is inserted without opening the door', by passing it into the ash-pit door and resting it upon the crossbearers as a purchase.

I claim as my inventionr l. A furnace-door constructed, supported, and arrangedAthat 1t may be opened either inwardly or outwardly, as herein set forth.

2. In combination with a furnace-door opening inward, of an inner inclined bed-plate, b', substantially as described, whereby the air is caused to pass through instead of over the fuel on the grate-bars.

3. In combination with a furnace-door opening both inward and outward, of a counter balance, substantially as and for the purpose described.

4. The air-openings c and the door a opening both inward and outward, in combination with the air-passages ff' and outlet-fines g g, substantially as herein set forth, and for the purpose stated.

5. The grate-bars h, of square cross-section.

having their front ends projecting outside of the furnace front, substantially as described, whereby they may be revolved upon their cross-bearers and lifted, withdrawn and replaced without opening the furnace-door, and keep their spaces.

6. The combination of grate-bars h, of square cross-section, and made to be revolved each independently of the other with knife-edgedV cross-bearers t', arranged as shown, and for the purpose described.

7. A furnace-door opening both inward and outward, with its frame and counter-balance, as a new article of trade and manufacture.

WILLIAM ARENA MARTIN.l

Vitnesses:

Ons. WUr'rEuMAsrne MARSHALL, J. B. WYNN,

24 Royal Exchange, Loudon. 

